This invention relates to reticles employed in optical systems and particularly to reticles employed in infra-red detector systems, and most particularly to a reticle-lens system which is effective in reducing back reflectance noise.
In a missile seeker system, for example, in which an infra-red detector is used as a guidance feature, a reticle is generally placed in the line of sight of the missile optics before the detecting circuitry. In prior reticles a problem existed when back reflectance in the reticle-lens system caused undesirable background noise.